Blow-out chute.



PATENIED MAY 24, 1904.

P.B.00RBY. BLOW-OUT CHUTE.

APPLICATION FILED 00T.16, 1902.

N0 MODEL.

{VIVEN-Vorig Fred COVQLJ QM/W aqttq.

UNITED STATE-s atented May Q4, 1904.

PATENT OFFICE.

ERED B. COREY, OE SCHENECTADY, NEW YORK, AssiGNOR TO GENERAL ELECTRICCOMPANY,- A CORPORATION OE NEW YORK.

BLOW-'OUT CHUTE.

SPECIFICATION forming part of Letters Patent N0. 760,850, dated May 24,1904.

Application filed October 16, 1902.

Be it known that I, FRED B. COREY, a citi- Zen of the United States,residing at Schenectady, county of Schenectady, State of New York, haveinvented certain new and useful Improvements in Blow-Out Chutes, ofwhich the following is a specification.

This invention relates to an inclosure fora fuse, a lightning-arrester,or any terminals between which an arc is liable to form, the inclosureconstituting a chutethrough which any arc formed between the terminalsor by the melting of the fuse is driven by the force` of magnetism inplates mounted on the sides of the inclosure. Devices of this kind,areI` usually made integral with the fuse or terminals whose arc theyare designed to extin guish, an electromagnet being provided whose fieldof force cuts the path of the arc. It is impossible to apply such amagnetic blow-out to an ordinary open-air fuse without furnishing acomplete device having terminalsl and blow-out combined. For many usessuch a, device would be of prohibitive cost. My device is a blow-outchute which may be applied to an ordinary open-air fuse or terminals andwhich is cheap in cost.

Magnetic blow-out chutes las heretofore constructed are provided with ablow-out coil to develop the field which extinguishes the arc, and asthe coils are connected in series with the terminals they'must be ofsuflicient cross-section to carry the entire current, thus requiring anexpensive coil containing much copper. In my device I dispense with theauxiliary coils entirely and develop the magnetic field solely by thepassage of the current through the fuse or between the terminals.' Iaccomplish this by mounting iron plates on or within the sides of theinclosure, and the current passing between these plates magnetizes them.This greatly reduces the cost of the device and conduces towardsimplicity and compactness. The general features are the same as in myapplication, Serial No. 121,714, filed September 2, 1902; but in mypresent invention is included only an inclosure adapted to be applied toand withdrawn from a fuse or terminals of any kind between which anSerial No. 127,456. (No model.)

arc is liable to form, `no terminals whatever being connected with theinclosure. In order to insure a complete extinction of the arc, I soarrange the magnetic field that the path of least reluctance is alwaysimmediately behind the are, causing a maximum concentration of the fieldat that point. rThis is simpl y effected by placing the magneticpole-pieces so that they extend oneither side of the path of the arc andshort-circuiting the lines of force on one side, so that a magneticfield is established only on the other side. Thus when an arc is formedthe field of force lies directly below the arc and repels the arcstream, and as the arc is stretched, duey tothe expulsive force of themagnetic field, this field follows it up until it is extinguished.

In carrying out my invention I make an inclosing chamber or chute of anynon-combustible material and mount within or on the outer sides of thesides of the inclosure metallic plates, such as iron, of highpermeability. These plates are so placed that they extend both above andbelow the line along which the current passes; but above that line.

and outside the inner walls of the chute I connect them with. iron yokesor rivets, which divert the lines of force from above the path of thecurrent, thus concentrating the magnetic field below that path only. Thecurrent passing between the plates magnetizes them, anda magnetic fieldis established across the air-gap below. the fuse or terminals. Shouldthe fuse blow or an arc strike across the terminals, the magnetic eldacting directly behind the arc bows it Outward; but as the arc bows thefield of force follows it up and bows it more and more until it isextinguished.

My invention therefore comprises a blowout chute to be applied to orwithdrawn from arcing-points in an electric circuit having iron platesmounted and overlapping on either side the line of passage of thecurrent and adapted to be magnetized by the current passing within thechute; and, further, it comprises means on one side for diverting orshort-circuiting the lines of force or reducing their density, thusestablishing a strong field at only one side of the line along which thecurrent passes.

In my former application, Serial No. 121,714, I showed a thermal cut-outwith blow-out chute and fuse complete ready for connection in a circuit.In my present application I include only the inclosing box or chuteadapted to be placed around or over any fuse er terminals that havealready been set up.

In the accompanying drawingsI have shown an embodiment of my inventionas placed around a fuse.

Figure 1 is a perspective view of the chute. Fig'. 2 is a longitudinalsection on the line fr; a', and Fig'. 3 a cross-section showing one endof one of the iron yokes connected to one of the plates.

In Figs. 2 and 3, A represents a fuse of any well-known type placedbetween the contactterminals B and B', which are connected in the maincircuit at M and N. C C are the sides, and D D the ends, of theinclosing chute and are made of fiber or other insulating' material. Setwithin the sides C C are the plates E E', Fig. 3, of wroughtiron orother material of high permeability. The shape of these plates is shownby the dotted line in Fig'. 2. They extend on either side of the fuseand are connected at their ends on one side by the yokes F F', which arealso of wrought-iron or other material of high permeability. H H arelugs'for securing` the inclosure to the same base that the fuse issecured to. rIhus a current passing from the terminal B across the fuseA to the terminal B magnetizes the.

plates E E', the magnetic lines of force being carried by the yoles F F,thus forming' a lield directly below the fuse. Should an abnormalcurrent pass across the fuse and melt it, thereby forming an arc acrossthe terminals, the magnetic iield would bow the arc upward more and moreuntilit broke and was extinguished.

W'hat I claim as new, and desire'to secure by Letters Patent of theUnited States, is-

1. A chute, open at its base to permit application overcircuit-terminals between which an are is liable to form and forming aninclosure for said terminals, having' plates of magnetic material at itssides polarized only by the passing of current within they chute.

2. A blow-out for electric arcs comprising an inclosure open at its baseto permit application about circuit-terminals and having plates ofmag'netic material mounted at its sides polarized by currents passing'between them and adapted to blow out any arc formed between the plates.

3. A removable inclosure for application about a 'fuse orarcing-terminals, having polepieces polarized by current passing' withinthe inclosure, said pole-pieces terminating in an air-gap at the rearoi' the path of the current.

4L. A removable inclosure for application about a fuse or the likehaving pole-pieces polarized by current passing within the inclosure,the pole-pieces being' so placed that the free poles overlap the line ofpassage ot' the current, whereby the magnetic lield which expels thearc-gases follows up the are stream.

5. A blow-out chute, open at both ends, arranged to be applied to andwithdrawn from circuit-terminals and having' a magnetic circuit of highpermeability with free poles at one side of the line of passage of thecurrent and a low-resistance magnetic shunt at the other side locatedoutside the inner chute-walls to prevent the establishment of a lield atthat point.

6. A blow-out chute consisting of an open box having' iron plates at itssides adapted to be applied to or withdrawn from circuit-terminals.

7. A blow-out chute consisting' of a box adapted to be applied to andwithdrawn from a fuse or circuit-terminals, said box having' iron platesin its side walls overlapping the level of the fuse.

8. A blow-out chute for electric arcs, comprising' a pair of iron platesrigidly mounted opposite each other and adapted to be applied to andwithdrawn from the arcing path, said plates being' arranged to extendbelow the level of the arcing path.

9. A blow-out chute for a fuse or the like consisting' of a pair ot'iron plates rigidly mounted opposite each other and adapted to extendbelow the level of the fuse one on either side thereof and to be appliedto and withdrawn therefrom, said plates being connected above thefuse-level by iron yolies.

10. A blow-out chute for a fuse or the like consisting of a pair of ironplates rigidly mounted opposite each other and adapted to extend belowthe level of the fuse one on either side thereofl and to be applied toand withdrawn therefrom, said plates being' connected above thefuse-level by iron yolies outside of the arc limits.

11. A blow-out chute consisting of a box adapted to be applied to andwithdrawn from a fuse or circuit-terminals, said box having' iron platesin its side Walls, tapering to increase the field density.

In witness whereotl I have hereunto set my hand this 14th day ofOctober, 1902.

FRED B. COREY.

Witnesses:

BENJAMIN B. HULL, HELEN OREORD.

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